Aluminum salts of alkylated phenol sulfides



Patented Jan. 10, 1956 ALUlVIINUM SALTS OF ALK' YLATED PHENOL SULFDJESPharis Miller, Mountainside, N. J., and Eugene Lieber, New York, N. Y.,assignors to Standard Oil Development Company, a corporation of DelawareNo Drawing. Original application December 27,

1939, Serial No. 311,118. Divided and this application October 18, 1944,Serial No. 559,255

10 Claims. (credo-44s) which may be written out more in detail asfollows:

If the various groups attached to the aromatic nucleus are so positionedthat the amyl group is in an ortho position to the oxygen and the sulfurlinkage is in a meta position to the oxygen, this compound, although itmight have other or potassium salts thereof, as by treatment with sodiumor potassium hydroxide and then converting the resultant derivative ofthe group I metal into the corresponding derivative of aluminum, bysuitable means such as by double decomposition of a, suitablecorresponding aluminum compound such as the chloride, nitrate, etc. Ifdesired, the alkyl phenol sulfide may be converted directly into thecorresponding aluminum salt by fusionwith a mixture of aluminum chlorideand sodium hydroxide, or by other means. Theinvention may be describedmore broadly as comprising a compound having an alkyl substituted arylaluminum oxide in which the oxygen of the aluminum oxide group isdirectly attached to the aryl nucleus and in which at least twoalkylated aryl nuclei are interconnected by at least one atom of anelement of the sulfur family, the alkyl radicals each containing atleast four carbon atoms. One or more of the unreplaced hydrogen atoms ofthe aryl nucleus maybe replaced by other elements, such as nitrogen,phosphorus, oxygen, sulfur and halogens; as in amino, nitro, phosphite,phosphate, hy-

p es, P b y has he following graphic 2:! droxy,-alkoxy, sulfide,thioether, mercapto, chloro formula:

groups, and the like.

cuau- 0-H ca! clHt- 0,11,, 0,11,,

s S B or, ifpreferred, by the group SS--, or even higher. polysulfidesmay be used. 7

= These various compounds can be produced by preparing the correspondingalkyl phenol sul-' fides or disulfides, which per se are known, andconverting these into the corresponding sodium The following formulasillustrate types of substituted phenolic compounds whose aluminum saltscan be prepared in accordance with the present invention:

The configurations of the compounds are not In this formula R representsone or more alkyl groups having enough carbon atoms, preferably atleast10, to insure solubility of the total compounds in mineral oil.

' For the objects stated, the metal phenolates have been preferablyprepared from phenolic compounds readily obtainable by syntheticalkylation of the simple phenols or by extraction from high boilingpetroleum oils.

Suitable synthetic alkyl phenols for preparing the desired phenolsulfides are principally of the secondary and tertiary types, becausealkylation of a simple phenol occurs more readily with branchedaliphatic reactants. Commonly, the alkylation reaction involves acondensation of olefins with the simple phenols, the reaction beingcatalyzed by anhydrous metal halides, sulfuric acid, phosphoric acid, orcertain activated clays,

As ole'finic" reactants, rcfinerygases containing propylene, butylenes,amylenes, etc., are coo-g nomically useful, although individual olefins,e. g.

isobutylene, iso-amylene, 'di-isobutylene, triiso butylene, etc. orolefin-containing mixtures from other sources may be used. The reactiontemperature is usually controlled to avoid side'reactions. In employingsulfuric acid, a liquid phase reac tion at relatively low temperaturesis preferred;

with phosphoric acid the reaction may be carried out in the vapor phase.

As starting materials for conversion into the .metal phenol sulfides,the phenols may cgntain one or more substituents which provide adesirednumber of saturated carbon atoms in groups having the form of straightchains, branched chains,

or even rings. Mono-alkyl or poly-alkyl phenols 4 the followingalkylated phenols, e. g., may be procured for preparing the phenolates:tert-amyl phenol, iso-hexyl phenol, tert-octyl phenol, ditert-butylphenol, etc.

Inorganic substituents are introduced into alkyl phenols by well knownmethods. For example, an alkyl phenol, e. g. tert-amyl phenol, isreacted with sulfur mono-chloride, SzClz, in about a 1:% mole ratio andpreferably ina solvent such as dichlorethane, to produce the alkylphenol disulfide. Using substantially the same procedure butsubstituting sulfur dichloride, $012, for the monochloride, the alkylphenols are given a thioether linkage substituent. Alkyl chlorphenolsare obtained by chlorination, preferably controlled to replace nuclearhydrogen by a chloro group. This maybe accomplished by chlorinating thephenol before alkylation; In such a manner, for example,2-chlor-4-tert-amyl phenol can be produced. Nitro substituents areintroduced readily into the aromatic nucleus by direct nitration, andnitro substituents can be reduced to amino groups.

. It is to be understood, however, that the preparaare synthesizedconveniently by alkylating 'a" phenol with a branched chain olefinpolymer,

such as diisobutylene, ditert-amylene, or other suitable agents, such asalcohols, alkyl sulfates,

alkylphosphates, or alkyl halides, thereby formleum phenols are obtainedby extraction of various stocks, chiefly from cracking process heatingoil stocks, with caustic soda, and acidification of the alkaline extractwith a weak mineral acid followed by a non-destructive distillation, ifdesired.

By using the described methods or any other well known method forpreparing alkyl phenols,

.tion of substituted phenolic compounds which Bil-parts by weighthhmble)of tertiaryamyl phenol .thioether (made according to U. S. Pat

ent2,139,321) were-dissolved in alcohol, and 5 parts by weight 'oi.analcoholic solution of potassium hydroxide were slowly added withstirring, and the resulting alcoholic solution'was evaporated to drynesson a steam bath. The residue was the potassium salt of -'-tertiary amylphenol thioether, which might otherwise be calledthe thioether of;tertiary amyl vllOtEtSsirmi phen aiteg; (Aslight exces oi the Phe iQ QBhEI w used tolinsure the absence of free alkali.)

ExarniJZeTZ l.

2,0 .partsby weight offthepotassium saltsof tertiary amyl phenolthioether, prepared as de-, scribed above 7 in, Example 1, weredissolved in absolute alcohol'arid 10.8 parts by weight oi aluminumnitrate, A1(NO3)3.9H20, dissolved in absolute alcohol were slowlyaddedto it. The

mixture wasevaporated to dryness and the residue was extracted withether, filtered and evap0- rated to dryness.

I The final residue was an aluminum salt;of tertiary amyl phenolthioether and it was solubleinoil. I l 4 v ,E r pl 3 zoo parts by weight(.51 mole) phenol thioether dissolved inabsolute alcohol,

were treated with 57.4 parts by weight (1-;0 mole) of. filteredalcoholic potassium hydroxide and the mixed solution was evaporated todryness on a steam bath. The product, although not as solublein minerallubricating oil as the potassium salts prepared in Example 1 by the useof a slight excess of the tertiary amyl phenol thio- Qiihfilk W 3 onvertdto thecorre'sponding alumis:

num salt by addingan alccholiesolution 'ofpar. tiailyv driedajaluminumnitrate to an alcoholic solution, of'the. potassiumisalt, using anexcess of the aluminum nitrate; Themixed solution was extracted withetherzandevaporated-to dryness."

of tertiary amyl v. Example 4 173 parts by weight of tertiary amylphenol thioether, 17.3 parts by weight of finely powdered sodiumhydroxide, and 40 parts, by weight, of anhydrousjaluminumpchloride, wereplaced in a 3-necked flask. The latter was heated to 150 C. withstirring, and the bath was heated at 130-150 0. over night withcontinuous stirring. The residue was dissolved in ether and the ethersolution was evaporated to dryness. Theproduct was soluble in mineraloil and contained a substantialproportion of aluminum salt of tertiaryamyl phenol thioether, although it apparentlywas not. quite as pure asthe, aluminum salt prepareddn Example 2-.

Example 5 The potassium salt of tertiary amyl phenol thioether wasprepared by neutralizing alcoholic solutions of potassium hydroxide andtertiary amyl phenol thioether as described above. Aluminum ethylate wasprepared by adding aluminum chloride to anhydrous ethyl alcohol. The twoalcohol solutions were mixed and then were allowed to stand on a waterbath, filtered free of the slight precipitate and evaporated to dryness.The product was the aluminum salt of tertiary amyl phenol thioether, andwas soluble in hydrocarbon oil. The product had the following chemicalanalysis, the theoretical value based upon the formula[(CsHinCsHs-OMSIQAI: bein also given for the sake of comparison:

Example 6 The sodium salt of tertiary amyl phenol thioether was preparedin the same manner as used for potassium salt as described in Example 1and the resulting sodium salt was treated with an absolute alcoholsolution of aluminum chloride. The aluminum salt of tertiary amyl phenolthioether was produced and was found to be soluble in a Diesel oilhaving a viscosity of 55 seconds Saybolt at 210 F. The sodium salt usedin the preparation of this aluminum compound had been prepared from ahighly purified distilled tertiary amyl phenol thioether.

This procedure was repeated using a plant grade or relatively crudetertiary amyl phenol thioether as the starting material, but theresulting aluminum salt of tertiary amyl phenol thioether was likewisefound to be soluble in the same Diesel oil.

Example 7 and dried.

Corresponding aluminum, etc. salts of other alkylphenolsulfides' may beprepared; for instance, by substituting polysulfides or polymers such asthe dimers, trimers, and tetramers, oi the alkyl phenol thioethers,disulfides, and the like, in place of the alkylphenol thioethers used inthe above examples. Also, the corresponding metal salts of thecorresponding selenides and tellurides maybe prepared, although thesulfur compounds are preferred.

The various products obtained may be purified, if desired, by fractionalcrystallization, extraction, precipitation with selective solvents, etc.Also, impurities may be removed by treatment with suitable adsorptiveagents such as clay.

The new compounds of the present invention are'useful as additives formineral lubricating oils, in which they are particularly effectivejininhibitingloxidationand the formation of sludge under the hightemperature conditions of service in internal combustion engines.

This invention is not to be limited to any of the specific examplespresented herein which were given solely for the purpose ofillustration, but only by the following claims in which it is desired toclaim all novelty inherent in the invention as far as the prior artpermits.

We claim:

1. As a new chemical compound, an alkyl substituted aryl aluminum oxidehaving the structure in which each of the three atoms of oxygen is anuclear attached oxygen of an alkyl phenol sulfid'e, the said alkylgroups containing at least four carbon atoms per molecule.

2. As a new chemical compound, an aluminum salt of an alkylated phenolsulfide having the formula in which the groups R, R, OH and S1: are eachconnected to an aromatic nucleus (CsHs), R and R represent alkyl groups(C'nHZfl-l-l), n being at least 4, and thereby rendering the said saltmiscible in mineral lubricating oil, and m is an integer, from 1 to 2,and in which all of the valences of the aluminum are satisfied by thealkylated phenol sulfide residues.

3. The aluminum salt of a tertiary amyl phenol sulfide in which all ofthe valences of aluminum are satisfied by the phenol sulfide residue.

4. An aluminum salt of an oil-soluble alkyl substituted phenol sulfide,each alkyl radical containing at least four aliphatic carbon atoms, inwhich all of the valences of the aluminum are satisfied by the phenolsulfide residues.

5. The method of preparing an aluminum salt of an alkyl phenol sulfidewhich comprises reacting an alkali metal salt of an alkyl phenol sulfidewith an inorganic acid salt of aluminum.

6. A method according to claim 5 in which the alkali metal salt is asalt of di-tert.-amyl phenol sulfide.

7. A process according to claim 5 in which the alkali metal salt is apotassium salt of di-tert. amyl phenol sulfide and in which theinorganic acid salt of aluminum is aluminum nitrate.

8. A method according to claim 5 in which the alkali metal salt is thesodium salt of di-tert. amyl phenol sulfide and in which the inorganicacid salt of aluminum is aluminum chloride.

REFERENCES CITED The fol-lowing references are of record in the file of1711-18 patent V UNITE STATES PATENTS I Date Number Name- 2,125,961Shoemaker Aug; 9,1938 2,139,321 Mikeska 1-; Dec; 6', 1938 2,207,719Cohen e17 a1. July 16 1940 Number 2,361,803 5 r 2,362,289 asses-'14Number 7 g Name.

, Date Shoemaker '.L Jan. 21, 1941 V Lightbprmetal'; 2-... Feb.9,. 1943'Wil'so'n' Oct. "'3-I',I944 Mikeske, Nov. 7; 1944 Reiif'rn Jan, 9, I945FOREIGN PATENTS v Country Date Great Britain -,Ja.n.- 1-5, 1932 7 Great.Britain. Apr. 8,1932 France 1-"- J uly 21,1932

-. ,flAddition to-. No-.. Tog-635) V e HER EREN Tasman; Gazette 011mmnfa'na a," vo1.. 1.'1. p.92(188 7).

1. AS A NEW CHEMICAL COMPOUND, AN ALKYL SUBSTITUED ARYL ALUMINUM OXIDEHAVING THE STRUCTURE